https://www.ncbi.nlm.nih.gov/books/NBK20255/>A conclusion that two (or more) genes or proteins are homologous is a conjecture, not an experimental fact. We would be able to know for a fact that genes are homologous only if we could directly explore their common ancestor and all intermediate forms. Since there is no fossil record of these extinct forms, a decision on homology between genes has to be made on the basis of the similarity between them, the only observable variable that can be expressed numerically and correlated with probability.

>>13816There are some fruit fly populations that are described as separate species and that do not (or cannot) interbreed, but which are genetically identical. It's a rather interesting anomaly that fedoras can't explain.

>>13801I know, right. It's hardly believable that from being almost flawless, having a error rate that is less than one mistake per billion nucleotides, bacteria develops into higher organisms that have shittier DNA replication. What kind of evolution is that?

>>13820There are even discrepancies in some nuclear genes in mammalian cells and for mitochondrial genes in plant cells. You can't physically prove that all organisms come from the same hypothetical ancestor in some ancient forgotten age billions of years ago.

Hemophilia is a good example of that. It's caused by a defective copy of a gene on the X chromosome and this tiny, marginal difference in one gene, of the 25,000 to 30,000 a person possess, is enough to create a lethal condition.

>>13844I'd bet you a dollar this is Davespiracy's /phi/ persona. He is a person uniquely capable of talking to himself as various 'different' people. He may be experimenting with avoiding replying to other people to avoid having to defend his inane, inconsistent posts.

I wish him success in this venture. The only person he should ever talk to is himself. At least that way he'll never look like the village idiot.

>>13830>You can't physically prove that all organisms come from the same hypothetical ancestor

True. They have no real arguments or experimental proof.

>>13836It is degeneration. Since this thread has shifted to examining chromosomal defects I might as well mention diastrophic dysplasia. It comes from an error in chromosome 5 and what's even more fascinating is that several diseases can occur if chromosome 5 is damaged (susceptibility
to diphtheria, Laron dwarfism, low-tone deafness and limb–girdle muscular dystrophy). To believe that bacteria turned into humans that are way more fragile when it comes to genetic sicknesses is the highest form of ignorance.

>>13856I'm pretty sure it's mostly one poorly programmed chatbot mindlessly drolling on against evolution; a couple of trolls trying desperately to equivocate belief in evolution to atheism; me chiming in every so often to remind everyone that evolution is a fact denied only by uneducated, mid-western, god-fearing rednecks; and perhaps one other poster who also sees what's going on, but is smart enough not to really bother doing anything about it.

Evolutionary studies are theoretical since they can't produce physical evidence.

Evolution is hard to believe in because it lacks proper explanation. If, for example, you look at venomous snakes and ask yourself how they got their neurotoxins you can't explain it through random mutations. Mutations, like another poster pointed out, are never beneficial and mostly causes defects so how do snakes suddenly develop glands filled with venom, hollow channels through their fangs that guides the poison all the way to the tip? It's too precise.

Another poster mentioned fruit flies and I think that's a valid point. Fruit flies, no matter how many generations pass, never become something else other than fruit flies. They don't develop a toxic coating on their exoskeleton to protect against predators. If you look at how effective poison is in defensive and offensive purposes in nature then all animals and insects should gradually develop poison glands but they don't.

Philosophically speaking evolution is not a scientific study, it's speculation. In mathematics 1+1 is always 2. But with evolution, 1+1, left alone for a period of time suddenly can become 4, 902, 57 000 or even -15. Obviously evolution doesn't have any fundamental rules that apply to all organisms because scientists can say that the diversity you see in this world is merely random.

>>13863Speaking of mutations...there are different mutations, by the way, like somstic and germ-line. Somatic mutation arises once in every million cell divisions, and so hundreds of millions of somatic mutations must arise in each person. Many somatic mutations have no obvious effect on the phenotype of the organism, because the function of the mutant cell, even the cell itself, is replaced by that of normal cells. However, cells with a somatic mutation that stimulates cell division can increase in number and spread. This type of mutation can give rise to cells with a selective advantage and is the basis for all cancers.

But germ-line mutation can be passed to future generations, producing individual organisms that carry the mutation in all their somatic and germ-line cells. When we speak of mutations in multi-cellular organisms we’re usually talking about germ-line mutations. In single-cell organisms there is no distinction between germ-line and somatic mutations, because cell division results in new individuals.

By default, bacteria should mutate more often, developing into new organisms by the millions but you still don't see bacteria evolving into other types of bacteria or even multi-cellular organisms for that matter.

>>13869I think microbial mats could be one basis of multicellular organisms. We know many kinds of bacteria and archaea can swap fragmnts of DNA, and these communities are very tightly knit. Just as cells absorbed mitochondria and integrated them forever after, perhaps some microbial communities decided to hook up permanently.

One thing we know for sure is that single celled organisms do evolve rapidly. How do you think we got superbugs?

If there's no such thing as evolution, then how does selective breeding work? We made all k8nds of dogs and cats by controlled mating and intervention in survival rates. How can you say te same mechanism doesn't work in nature: those who survive to breeding define their species, one way or another.

Why do I even bother... This robot isn't going to reply and some troll is going to think I'm an atheist, even though I think atheists are stupid too.

>>13869>bacteria should mutate more often, developing into new organisms by the millions but you still don't see bacteria evolving into other types of bacteria or even multi-cellular organisms for that matter.

That kind of relates to my earlier post. Mathematically, the probability of single-cell organisms transforming into a duck or even a fish is practically nil.

>>13869That's probably the greatest conflation fedoras make when talking about mutations. As an example, HIV’s reverse transcriptase is very error prone, giving the virus a high mutation rate and allowing it to mutate rapidly within a single host. This rapid mutation makes the development of an effective vaccine against HIV very difficult.

Fedora tippers say this proves evolution is real according to their mental gymnastics. But it doesn't. All it does is prove that HIV rearranges its nucleotides. It doesn't evolve into something else. It's still HIV.

The same process could be said about a common cold. You can't develop a vaccine against it because it changes its nucleotide sequence and it's still a common cold.